Stress intensity factor solutions for several crack problems using the proportional crack opening displacements

A general finite element procedure based on the proportional crack opening displacements for obtaining the stress intensity factors is presented. The procedure is applied to the nonsingular 3-node linear, 4-node linear, 8-node parabolic, 8-node axisymmetric elements and 8-node hexahedral solid elements for a test. It is found that the current method exhibits good element type adaptability and significantly less mesh dependency, and accurate results can be obtained effectively using rather coarse meshes. The accuracy of the current procedure is evaluated by applying it to two-dimensional interface cracks, three-dimensional penny-shaped cracks as well as circumferential surface cracks. Comparison with the published data from the literature shows that the current procedure gives accurate stress intensity factors. Furthermore, the current method is fairly efficient and less computational resource consuming and can be used as an effective tool in the reliability analysis of the bonded multi-layers.